The present invention relates generally to the field of entertainment device controls, and also their associated visual displays. More particularly, the present invention relates to audio controls for a radio, and displays associated with these audio controls, wherein preferably the radio is electronically pushbutton tunable and is intended for use in an automobile.
Typically, automobile radios have been limited in the number of audio control features and the number of visual displays since only a limited amount of manual control and display space is available in the automobile dashboard for the front control panel of the radio. Thus, to accommodate a large number of audio controls and/or a large number of different displays, the displays and controls would have to be made objectionably small thereby hindering efficient control of the radio by the operator and compromising the effectiveness of the visual displays. In addition, providing a large number of different control buttons for an automobile radio is not desirable since such radios, by necessity, must be controllable with a minimum amount of attention from the operator who may be driving the automobile at the same time that he is attempting to adjust the radio controls. Because of the aforesaid problems, typically automobile radios have not provided a device having a large number of audio control functions and their associated displays without extensively comprising the desired size and complexity of the radio controls and displays.
Generally, in order to minimize the number of controls on the front control panel of the automobile radio, such radios have utilized concentric shaft potentiometers to control balance and fader modes of operation for the radio. Some prior radios have utilized up/down pushbuttons to control the volume of the radio, and this actually represents a step backwards since now two pushbuttons are utilized to replace a single control shaft for a volume potentiometer. These prior art devices have been unable to implement a large number of audio controls and their associated visual displays within the space restraints imposed upon automobile in-dash radios without extensively comprising desired size and complexity characteristics for the controls.
In copending U.S. application Ser. No. 114,018, filed Jan. 21, 1980, and entitled "Radio with Audio Graphic Equalizer", which is assigned to the same assignee as the present invention, a radio is disclosed in which each of the channel recall tuning pushbuttons can operate as a band selector for an audio graphic equalizer wherein the actual adjustment of the audio emphasis provided to the selected band is controlled by actuation of up/down tuning pushbuttons when an equalizer mode of operation is selected for the radio. This radio also contemplates using the tuning display to display the equalizer frequency response in the equalizer mode. While this radio does eliminate a number of audio controls and their associated displays, the present invention represents a vast improvement to this radio in that a substantial number of additional audio controls are implemented without any substantial increase in the number of manually actuable radio controls and without the necessity of requiring a large number of separate and additional audio control displays.